Means for preventing the jamming of machine-guns



W. THOMPSON. MEANS FOR PREVENTING THE JAMMING OF MACHINE GUNS.

' APPLICATION FILED AUG-12, I918.

Patented '15, 1921.

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UNITED STATES WALTER THOMPSON,- or BROOKLYN, NEW YORK.

MEANS FOR PREVENTING- THE JAMMING OF iMiACfiIN'E GUNsa To all whom it may concern:

Be it known that I,WALTER THOMPSON,

' subject of the King of Great Britain, residing at Brooklyn, in the county of Kings and State ofNew York, have invented'new and useful Improvements in Means for Preventing the Jamming of Machine-Guns, of which the; following is a specification.

My invention relates more particularly to means for preventing the jamming of ma- I chine guns.

Cne of the, difiiculties in the successful operations of automatic or semi automatic ns such, for instance, as machine guns, is

that due to the jamming of the gun mech-" anism, rendering the gun useless until the jammed condition is overcome. I v 7 'I have discovered that one of the main causes of; this difiiculty is the tendency of the percussion cap to be displaced from its seat thus disturbingfthe operating conditions in such manner as to prevent the normal-functioning of the operating mechanisi n; s 7 V This displacement may take place, inv any one of a number ofstages and lead to jamming. Forinstance, it may occur in feeding and aflI'ect the feeding'operation or prevent proper firing-and thus prevent proper operation ofthe ejecting machanism. But the principal cause of such difiiculty is due to the direct of the firing of the cartridge, the expansion of gases tending to displace the cap from its seat in the cartridge base, thus affecting the operating mechanlsm and producing the jam, as by changing the general configuration of the base to vary it from that required for cooperation; with the firing and ejecting'mechanisms, or-by forcing thecap away from the seat and into the operating mechanism thereby jamming the latter; r This displacement of the cap. is made possible' by the difiiculty presented in initially positioning thejpercussion cap, this positioning being ha'df mainly by automatic Inachinery and subject to Possible imperfec-s tifons', together with the difiiculties; of inspection. to determine, the certainty of proper anchorageoiflie. caP r The present invention is de'signedtof meet this-probl m by pos ively a ch ring e 'p j against} displacement, and a, preferred way .isjtoj up e h 'Ina e' i l the. r ridge, ba

intdananchorin'gformation relative'to the specification of Letters Patent.

Patented Mar.1 5, 1921.

Application filed August. 12, 1918. Serial No. 249,397.

positioned cap. .This may be provided in advanced the location of the cartridge in the feeding mechanism of the gun-as, for instance, at the timeof cartridge manufacture-0 this anchoring 3 formation maybe providedwithin the gunmechanism as, for lnstance, concurrently with :the' striking-pf thecap so that the anchor is formedto withstand the efi'ects of the gas expansion.

Ineither case, the cartridge shell has its percussion cap anchoredagainst, displacement' relative to its seat, this anchoragebe' ing present when-the cartridge has been fired, and may be present in advance of the firing in case the anchorage is formed prior to locating the cartridgein the gun To these and other ends, the nature of which will be readily understood asthe inventionis hereinafter disclosed,sa id inven-- tion 'consists'in the-improved construction and arrangement of parts hereinafterfully described, illustrated in the accompanying drawings, and more particularly pointed out in the appended claims. v

In the accompanying drawings, in which similar reference characters indicate similar parts in each of theviews o Figure 1 is a view partly i section and partly in elevation of portions of a firing mechanism of a standard machine gunconstruction.

Fig. 2. is a view partly in section and partly in elevation of the firing mechanism.

Fig. 3 is an enlarged detail view of a portion, of the firing pin, showing one wayv in which the anchorage maybe provided, parts being broken away for clearnes's.

Fig. 4 is "a perspective view of a cartridge shell showing the percussion. cap anchored 1 The solution. of the. proble 'wh fi provided by the. present invention] consists anchoring the'percussion cap against displacement from. its. seat the cartridge I b se; this T being preferably provid d by .up-

setting the metal, of the .base' into'an anchorage formation relative to thecap This issho'wn in Fig. 4 in which 10 indicates the cartridge base, generally of metal and 11 indicatins the uercussion ca aositioned in the base, the latter carrying the seat for the cap. As shown in this view, the metal of the base adjacent to the perimeter of the cap has been upset, as at 12, so as to. carry this upset portion over into the path of.

As heretofore pointed out,- this anchoring formation may be provided at the time when the cartridge or cartridge base is being manufactured, or it 'may be provided subsequent thereto, since the upsetting opera tion is of a character which does nottend to fire the cap. When produced during the manufacture, the cartridge carries the dis-.

placement-preventing means in advance of use, with the means so formed as-to notaffoot the ability ofthecartridge to beflused in any desired fire arm. I

The'invention however'is'not'limited to the production of this anchor format-ion in ad Vance of'positioningin the fire arm,sinc'e the formation may be provided during firing operations. Forinstance, in Figs. 1 to*3 I have shown parts of a standard machine gun, the firing pin 13 of which carries one or more elements or devices 14- which serve to produce this upsetting action at the time when the pin is operating in connection with the percussion cap. The device is is shown as in the form of an upsetting element which is brought into contact with the base of the cartridge by the movement of the firing pin and at a point in proximity to the base opening within which the cap is seated, Fig. 3 showing the general action of the device at this time. 7 p j No detail description of the particular gun mechanism shown is given since the invention is applicable to different types of machine guns, and may, if desired, beutilized in connection with the ordinary rifle or gun orany of the automatic or 'semiau-. tomatic guns in general use, these all operating with firin pins of different types." I

It will be un erstood, therefore, that the general invention is not limited to the par ticular time of production of the anchor formation nor the particular mechanism which may be employed in producing it,-

since, 'as above pointed outfit may be produced at the time'offcartridge manufacture by mechanism other than the mechanism of the gun, or it may be produced at the timeof cartridge use and by mechanism carried by and forming a part of thegun mechanism.

7 N or is the invention limited to its use, in

matic orSemi-autOmatiC conditions where jamming of-the gunbecomes a critical difficulty. 3

While I have herein shown and described preferred ways in which the invention may be carried out, itwill be readily understood that changes and modifications therein may be found essential ordesirable in meeting the individual conditions of use, and I desire tobe understood as reserving the right to make any and allsuch' changes or modifications as may be found desirable or essential, in'so far as the same may fall within the spirit and scope of the invention as exprcssed in the accompanying claims when broadly construed. i i

1 What I claim-is:

1. In a gun adapted to fire a cartridge provided witha percussion cap, means for holding the cartridge in firing position including a breech blofclc and means movable relative to the breech block operative during firing upon the cartridge shell to prevent displacement ofthe percussion cap. 2. In a gun adapted to'fire' a'ca-rtridge provided with a-percussion cap, means for holding the-cartridge firing position including a breech block and means movable relative to'the breech block-'foperative during firing to force a portion of the'cartridge base into position behind the to anchor said cap in place.

In automatic or semi-automatic gun operation wherein the cartridge is fired by a firing pin, means'for preventing jamming of the gun'by anchoring the percussion-cap to its seat inthe cartridge base, said means comprisinga device movable withsaid pin and operative .to upset metal of thebase into an anchoring formation relative to'the cap. 4. ln agun adapted to fireflacartridge provided with a percussion cap,means for holding the cartridge in firing position in clu'ding a breech block and means 'movable relative to the breech block operative during firingfor strikingup a portion ofthe cartridge shell adjacent the percussion oapto' block, a firing pin and means shiftable relative to said breech block into engagement with saidcartridge shell base simultaneously "with the impact of the firing pin on the percussion cap to force said base into engagementwith the cap to retainit in position in thebase. 1 .1.

"6. In combination, machine gun firing mechanism including a firing pin adapted to fire a positioned cartridge by striking the p percussion cap 1,371,527 i g v ed to force the base of said cartridge into' engagement with the cap to retainit in po- 10 sition in the base. r

8. In a gun adapted to fire a cartridge provided with a percussion cap, a firing'pin I I and means rigidly connected to and moving 7 with the firing pin, adapted to force the base 15 of said cartridge into engagement with the cap to retain it-in position in the base.

WALTER THOMPSON. 

